Enable Data Transfer Protocol

How to enable Data Transfer Protocol.

The NameNode gives the client the address of the first
DataNode to read or write the block. The actual data transfer between the client and the
DataNode is over Hadoop's Data Transfer Protocol. To encrypt this protocol you must set
dfs.encryt.data.transfer=true on the NameNode and all DataNodes.
The actual algorithm used for encryption can be customized with
dfs.encrypt.data.transfer.algorithm set to either "3des" or "rc4".
If nothing is set, then the default on the system is used (usually 3DES.) While 3DES is
more cryptographically secure, RC4 is substantially faster.

Enable Encrypted DTP by setting the following properties in
hdfs-site.xml: